\section{Application}
\label{sec:application}
 After introducing our APIs, we will show two
real applications which can be easily implements by composing our
APIs. For each application, we will first introducing what it is.
Then we will show how we build these applications by using our APIs.

\subsection{Nokia's Photo Sharing Project} This project is an
researching project from Nokia Research Center which aims at
building a photo management application. It is also called kaleido
photo. The application mainly contain three tasks.

\begin{enumerate}
\item Photo clustering: When the user build an album, the application can
automatically select out the related photos and put them into the
album.
\item Photo searching: The user has taken many photos in a party but
they are messed up with other photos. Provided with the time,
location or calender event information, the application can help
user selected out such photos.
\item Photo recommendation: The user wants to recommend some photos
to his/her friend. The application will help the user to figure out
which photo is related to the friend and is suitable for the
recommendation
\end{enumerate}

For the first two tasks,



\subsection{Probability Model Based Recommendation System}
